Impossible to implement LanguageServiceHost::resolveModuleNames without using TS internal getModeForResolutionAtIndex

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Suggestion

🔍 Search Terms

LanguageServiceHost
resolveModuleNames
getModeForResolutionAtIndex

✅ Viability Checklist

My suggestion meets these guidelines:

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, new syntax sugar for JS, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.

⭐ Suggestion

Expose ts.getModeForResolutionAtIndex as part of public API, or otherwise provide a way to implement LanguageServiceHost::resolveModuleNames with full NodeNext compatibility.

Alternatively, I might be wrong if there is a different correct way to implement resolveModuleNames.

📃 Motivating Example

This attempted bugfix, where I am using ts.getModeForResolutionAtIndex within my implementation of LanguageServiceHost::resolveModuleNames
TypeStrong/ts-node#1782
Link to the invocation of getModeForResolutionAtIndex https://github.com/TypeStrong/ts-node/pull/1782/files#diff-c654137f603e726b39295587f26aee8130da50d8c019ba7e176b201917f17e56R101-R107

💻 Use Cases

ts-node, which JIT compiles and typechecks using the LanguageService, and supports NodeNext